The present invention relates to propulsion and gas generating systems which utilize solid fuel.
In the current state of the art, either liquid or solid fuel, or propellant, is used in propulsion systems. Liquid fuel can easily be introduced at a controlled rate into a combustion chamber in order to allow the propulsion energy level to be adjusted in a simple manner. In addition, combustion can be halted and restarted simply by stopping and restarting the flow of liquid fuel into the combustion chamber.
However, liquid fuels tend to be relatively toxic, creating both storage and environmental safety problems, as well as some risk of destructive malfunction of the propulsion system in which they are employed. Furthermore, known liquid propellants have a lower energy density than do solid propellants.
However, solid propellants, despite their inherent advantages, do not lend themselves to controllable propulsion requirements or to controlled shut-off when intermittent propulsion is desired.
The present invention provides an improved method of producing a controlled combustion, comprising: placing a combustion chamber in communication with a feed tube or chamber that contains a solid propellant body; introducing at least a portion of the body into the combustion chamber; isolating the combustion chamber from the feed chamber; and igniting the solid propellant in the combustion chamber while the combustion chamber is isolated from the feed chamber.
The invention further provides a novel device for producing a controlled combustion, comprising: a combustion chamber; a feed chamber containing a solid propellant; an outlet from the combustion chamber in communication with either a nozzle or an accumulator; an igniter communicating with the combustion chamber; and displacement means coupled to one of the chambers for establishing a first position in which the combustion chamber in communication with the feed chamber to allow at least a portion of the solid propellant to be introduced into the combustion chamber, and a second position in which the combustion chamber is isolated from the feed chamber and in communication with the outlet nozzle.